1. Field of the Invention
The present invention relates to a vehicle lighting device of a so called projector type, using a semiconductor-type light source, such as an LED, as a light source.
2. Description of the Related Art
A vehicle lighting device of this type is conventionally known (Japanese Laid-open Patent Application No. 2008-77890, for example). Hereinafter, the conventional vehicle lighting device will be described. The conventional vehicle headlamp is made up of: a projecting lens; a light source; a reflector; an additional reflector; and a shading portion. When the light source is lit, the light from the light source is reflected by means of the reflector, and a part of the reflected light is cut off by means of the additional reflector. The remaining one of the reflected light, which has not been cut off, advances to the projecting lens side. The cut off reflected light is further reflected on the projector lens side by means of the additional reflector, and a light distribution pattern having a cutoff line is illuminated from the projecting lens toward a forward direction of a vehicle. The conventional vehicle lighting device is capable of performing smooth dimming as to a part at a downside of the cutoff line of the light distribution pattern by means of the shading portion.
However, the conventional vehicle headlamp allows the shading portion to shade a part of the reflected light from the reflector and a part of the reflected light from the additional reflector, thus removing the light at a part at the downside of the cutoff line of the light distribution pattern. As a result, as to the light distribution pattern, there is a great difference in light intensity between a portion through which the light has passed and its periphery, and it is difficult to smoothly perform dimming.
The present invention has been made in order to solve the above-described problem, i.e., in order to overcome the difficulty in smoothly dimming a part at the downside of the cutoff line of the light distribution pattern in the conventional vehicle lighting device.